Effects of Obesity on Balance Recovery in Response to Small Postural Perturbations

Obesity is a major and growing health concern associated with an increased risk of falls. The majority of falls are thought to result from some kind of postural perturbation, yet the biomechanical mechanisms as to why obese individuals fall more often is unclear. Therefore, the goal of this study was to investigate the effects of obesity on balance recovery in response to small forward postural perturbations. Twenty male participants, including 10 lean (mean BMI ± SD: 21.9 ± 1.4) and 10 obese (BMI: 33.2 ± 2.3), were exposed to two types of postural perturbations (force impulses applied with a pendulum and angular displacements administered with a release mechanism). Participants attempted to recover balance with only an ankle strategy such that neither a step nor hip flexion was utilized. Quiet standing trials were also conducted for comparison with the literature. Obese individuals exhibited less center of mass (COM) displacement and a slower COM velocity compared to lean individuals when exposed to identical force perturbations. When exposed to the force perturbations relative to body weight, and when released from identical lean angles, no differences in COM performance were found. During quiet standing, no differences in center of pressure (COP) velocity were observed between obese and lean groups. In all tasks, the obese generated higher ankle torque than the lean. Overall, the obese participants exhibited no differences in movement or less/slower movement than the lean participants when recovering from small forward postural perturbations as well as during quiet standing. These results imply that obesity in young adult males did not impair balance recovery for the tasks investigated.

Name thesis:degree_name

Master of Science

Level thesis:degree_level

masters

Discipline thesis:degree_discipline

Biomedical Engineering

Department dc:contributor.department

Biomedical Engineering

Grantor dc:publisher

Virginia Tech

Year dc:date.issued

2008

Author dc:creator

• Miller, Emily Michele

Chair dc:contributor.committeechair

• Madigan, Michael L.

Committee members dc:contributor.committeemember

• Gabler, Hampton Clay
• Lockhart, Thurmon E.

• Obesity
• postural perturbation
• balance recovery

Statement dc:rights

• In Copyright

Licence dc:rights.uri

• http://rightsstatements.org/vocab/InC/1.0/

Dc Identifier Other

etd-10222008-141157

OAI identifier oai:identifier

oai:vtechworks.lib.vt.edu:10919/35465